Les Blank, the poetic documentary filmmaker who gave voice to the obscure and gap-toothed, died Sunday at his home in the Berkeley hills.

He was 77 and the cause of death was bladder cancer, said his son, Harrod Blank.

Over a span of 40 years, Mr. Blank averaged a film a year. He covered topics ranging from Afro-Cuban drummers to Appalachian fiddlers to flower children to a search for the perfect tea leaf in China. One work, 1980's "Garlic Is as Good as Ten Mothers," was screened accompanied by an in-theater roaster, introducing the phenomenon of "Aromaround" to theater audiences.

"Les Blank represents the choicest inspiration that a documentarian can have. He followed his interest and his heart and his passion," said Taylor Hackford, president of the Directors Guild of America, who met Blank back when he was living in a garden shed behind a Hollywood bungalow. "Les doesn't care how much money he has. He is bound to deliver on film exactly what he sees, and that is unique."

Mr. Blank was the first documentary filmmaker to earn the Edward MacDowell Medal, a national honor given to just one artist a year. He was also awarded the American Film Institute Maya Deren Award for outstanding lifetime achievement as an independent filmmaker. He was recently celebrated at the "Les Fest," and on Jan. 22 he was honored at Les Blank Day in Berkeley, where he lived for more than 30 years.

Remarkable debut

"I started showing Les' films in 1969 when I saw his first film, 'The Blues Accordin' to Lightnin' Hopkins,' " said Tom Luddy, a longtime producer for American Zoetrope and co-founder of the Telluride Film Festival. "I thought it was the best film on music I had ever seen. He got stuff that nobody else gets."

Luddy thought it was a fluke, but it wasn't. "That began this amazing career of capturing the culture and lifestyle of so many unique artists working in regional American settings." Leslie Harrod Blank Jr. was born Nov. 27, 1935, in Tampa, Fla. At age 16 he was shipped off to boarding school at Phillips Academy in Andover, Mass. He earned his bachelor's in English and master's in fine arts at Tulane University, then came west on a fellowship to study theater and cinema at USC.

On-the-job training

Blank found work making industrial films, which also provided on-the-job training for his documentary career. For his first, he went to Texas to immerse himself in the world of Sam John Hopkins, a guitarist known as "Lightnin'." Wherever he filmed Lightnin', Blank was generally the only white person, and he developed a strategy of staying as still and quiet as possible for as long as possible, in hopes his subjects would forget he was there. When the film came out in 1969, "people took notice because it was something they had never seen before," Luddy said.

This was in the days before independent film, and the 31-minute portrait was shown at festivals, museums and on television, launching Blank's career.

He moved north into the Berkeley home of Luddy, who was then running the Pacific Film Archive. Luddy introduced Blank to filmmaker Werner Herzog, and the documentary filmmaker ended up making "Burden of Dreams" (1982) about Herzog. That film won "Best of Festival" at the San Francisco International Film Festival and was named the best feature documentary by the British Academy of Film and Television Arts.

In 1976, Blank partnered with Chris Strachwitz of Arhoolie Records to form Brazos Films and make three documentaries: "Chulas Fronteras," about Tex-Mex music on the border; "Del Mero Corazon" about borderland love songs; and "J'ai Ete Au Bale," about the Cajun and Creole culture in Louisiana.

"He had a wonderful, extraordinary eye," said Strachwitz, whose tight time and money frame was often at odds with Blank's "fly on the wall" filmmaking strategy.

"Sometimes he sat in a damned field of flowers and just filmed the flowers when I was ready to go to the next musical event," recalled Strachwitz. "His aesthetic was to just sit calmly back and watch people do what they do rather than to be aggressive and get an overall project going."

Breadth of interests

The film titles alone indicate the breadth of Mr. Blank's eccentric interests, starting with "Running Around Like a Chicken With Its Head Cut Off," made while he was a student at USC, released in 1960 and still in circulation. The works include "God Respects Us When We Work But Loves Us When We Dance," "Dry Wood," "Hot Pepper," "In Heaven There Is No Beer?" "Cigarette Blues," and "Gap-Toothed Women."

"No one had ever seen a film about women with a gap in their front teeth," said Harrod Blank. "Les always told me a movie should be something you want to watch. Even though it is a documentary, it has to move the audience."

His most recent release, "All in This Tea," came out in 2007, the year Mr. Blank was nominated for the MacDowell Medal, affiliated with the MacDowell Colony, the prominent artists organization based in New Hampshire. A filmmaker is awarded every fourth year, and it usually is given to a conceptual artist.

But in 2007, Hackford was the chair of the awards committee and made a forceful pitch. "I said 'Les Blank is a national resource. He is a wonder. He puts on film something that is going to live forever.' "

Mr. Blank was married and divorced three times, the first while he was still a student at Tulane. With his third wife, anthropologist Chris Simon, he bought a home on Summer Street, with Codornices Creek running through the backyard.

Mr. Blank kept his mustache waxed and kept himself in shape, but he also smoked three packs a day in his youth. He quit in his early 40s, but the effects caught up with him in May when he was diagnosed with bladder cancer. Mr. Blank blamed the smoking.

"Every day he would hike the neighborhoods of Berkeley. That's why he is here. He liked to go on major hikes on the weekend," said Harrod Blank.

His last hike in Tilden Park was in July, and even as his health failed he was walking around the block, usually accompanied by one of his sons, or his ex-wife and caregiver Simon.

"He kept walking until he just couldn't walk anymore," said Harrod Blank.

Final projects

He kept working, too. At the time of his death, he had two projects going, one on an Alabama folk artist and the other on a fellow documentarian.

"Those films just need to be edited," said Harrod Blank. "If he kept living, that would have happened in the next year or two."

Last summer he had a major retrospective at the Pacific Film Archive. Every Sunday, he appeared to introduce a different film and answer questions. Film colleagues and family recently crowded into the theater at Fantasy Studios for "Les Fest," a montage of his best-known and most-loved clips.

"It summarized some of his amazing accomplishments," said Strachwitz, who was there. "We celebrated his work, which will live on."

Mr. Blank is survived by his sons Harrod, of Douglas, Ariz., and Beau, of Washington, D.C.; daughter Ferris Robinson of Lookout Mountain, Ga.; and three grandchildren.